In drink preparation means for dispensing drinks, and in particular for dispensing hot drinks such as coffee and hot chocolate, powdered ingredient is often used, which ingredient, when mixed with hot water, produces the drink. This powdered ingredient is stored in the means in a holder which is provided at the bottom with a conveyor mechanism with which the ingredient is guided via an outflow system in the form of a tube or chute to the filling opening of a mixing unit. In the mixing unit the ingredient is then mixed with water and usually also dissolved in the water, after which it flows out of the mixing unit into a collection reservoir such as a cup, a beaker or a jug. A drink preparation means of this type, in particular the mixing unit thereof, is described in WO-03/068039 and also in NL 2000164 which has not yet been published.
Drink preparation means of this type generally have to be cleaned and maintained regularly, in many cases even every day. For this purpose, the mixing unit or mixing units can be wholly or partly disassembled or removed from the drink preparation means. The ingredient holder or ingredient holders can also be removed from the drink preparation means, either to clean them or to be able to fill them with powdered ingredient more easily.
During maintenance of the drink preparation means or when the ingredient holder is removed from the drink preparation means, it is convenient if the outlet of the holder can be shut off. Additionally, it is advantageous in the outflow system (connecting the holder to the mixing unit) can be placed aside.
In order to be able to shut off the outlet of the holder, the outflow systems of known drink preparation means are usually provided with a shut-off valve. This shut-off valve conventionally consists of either a rotatable part, which can be rotated from a position located outside the passage of the outflow system into the passage of the outflow system in such a way that this passage is shut off, or a slide which can be slid at right angles to the throughflow direction of the outflow system into the passage of the outflow system in order thus to shut off this passage.
In shut-off valves of this type the powdered ingredient accumulates against the shut-off member on the side of the holder that is located upstream of the shut-off member. Along the shut-off member this accumulation of powdered ingredient forms a straight plane which is at right angles to the throughflow direction of the outflow system. When the shut-off valve is opened, the powder will start to slide off in this square plane, as a result of which a portion of the powder will enter the mixing unit via the remainder of the outflow system.
For setting aside the outflow system, it is known to configure this outflow system so as to be rotatable with respect to the holder, thus allowing it to be twisted off. In practice, twisting-off of the outflow system has also been found to cause accidental detachment of powder from the accumulation upstream of the shut-off valve, the powder then entering the mixing unit via the outflow system. A further drawback of the known shut-off valves is that it is easy to forget to reopen the shut-off valve prior to normal operation. If the conveyor means (usually a conveyor screw) at the bottom of the holder then starts to convey powder in the downstream direction of the outflow system, this powder is then unable to escape as a result of the closed shut-off valve. This then causes the shut-off valve, the conveyor means or other components to break or—in a more beneficial case—the powder to take a different escape route and enter not the mixing unit but rather a different part of the drink preparation, and this is not desirable either.
The object of the present invention is to improve the capacity to shut off the outflow system, in particular the outflow channel thereof provided on the holder. The aim of this is to minimize uncontrolled dispensing of spilt powdered ingredient from the holder.